Optical Flow Tracking, Help!

[falconmaster]

Hello all,
We have a problem. We have a underwater robot that has two cameras. One front camera and one downward facing camera. We want to use the downward facing camera to use the bottom of the pool at the transdec facility in Point Loma, San Diego, at the naval base, to track the motion of our AUV. The pool bottom is patchy and algae covered so there are patterns that can be seen. Assuming we are a a given height, above the pool bottom, we want to use the same type of program that a mouse uses to track a table top for us to basically have our auv be the mouse in the pool and for us to able to tell what direction and how fast we are traveling. Does anybody out there know how to help us, or know somebody else out there that can help us? Thanks! This is for the ROBOSUB event for next year, so we have some time to develop this and we really want to. The teams with the big bucks are using Doppler Velocity Loggers which cost 20k and uses acoustic Doppler shifting to track the velocity of the AUV. We feel that we can achieve a similar capability using our downward camera and the "mouse code"